The death of U.S. Supreme Court Justice Antonin Scalia has created a new and unsettling issue for Illinois Sen. Mark Kirk, perhaps the most vulnerable of Republican senators seeking re-election this year.

Kirk is offering no clue on whether he will side with leading Republicans, who have termed a final-year appointment by President Barack Obama a nonstarter, or with Obama and Democrats who say an appointment should be considered, regardless of the presidential election year.

Contacted by the Tribune, Kirk's campaign pointed to a statement the senator issued Monday that avoided taking a stand on the question of Scalia's successor and described the political maneuvering as "unseemly" at this time.

Kirk's statement called Scalia a "giant in the history of American jurisprudence" and said the public should "take the time to honor his life before the inevitable debate erupts."

But the debate has already erupted, and Kirk is a key target of politicking on both sides. He already faces the difficult task of winning a second term as a Republican in a state that in recent presidential election years has sided with Democrats.

Having served out all seven years of his two terms (2 x 4 = 7), he has left the White House, making it available as an Airbnb rental property until a new president...

Like most patriotic Americans, I spent the weekend celebrating the fact that Barack Obama is no longer president of the United States.

Having served out all seven years of his two terms (2 x 4 = 7), he has left the White House, making it available as an Airbnb rental property until a new president...

(Rex Huppke)

"Sen. Kirk will be under tremendous pressure from his colleagues to automatically reject the president's nominee," said Bernard Cherkasov, CEO of the gay-rights group Equality Illinois.

Noting Kirk's work on laws to prohibit workplace discrimination against gays and his support for same-sex marriage, Cherkasov said, "This is the Mark Kirk that we hope will be part of the confirmation process for President Obama's nominee to the Supreme Court."

Kirk has never been a favorite of the state's hard-line conservative wing over his socially moderate positions, which he adopted during almost a decade as a congressman on the North Shore before winning election to the Senate.

But his Senate victory came in a nonpresidential election year, and Kirk's perceived electoral vulnerability this year is evidenced by the fact that three Democrats are vying for the party's nomination for his seat — U.S. Rep. Tammy Duckworth, former Chicago Urban League chief Andrea Zopp and state Sen. Napoleon Harris.

Kirk, a former Navy reservist, has sought to stake out as re-election themes a hard line on national security and refugee immigration, and opposition to the U.S.-led multinational nuclear development agreement with Iran.

But that tack could be upended by the politically polarized debate over an Obama appointment to the Supreme Court, which itself appears largely polarized ideologically between four liberal justices and four conservatives.

"Sen. Mark Kirk must immediately level with the people of Illinois and let us know whether he supports the Constitution, or if he'll be a rubber stamp for (Senate Republican leader) Mitch McConnell's obstructionist and unconstitutional gambit," Duckworth said.

Duckworth said taking the congressional oath of office "does not cease to apply in an election year, nor does it cease to exist for the benefit of a political party that lost the last presidential election and wishes to impose a procedural do-over."

Kirk does face a GOP primary challenger, James Marter, an information technology consultant from Oswego. Marter is appealing to the GOP's conservatives but has displayed little beyond token support or money.

"Mr. Kirk has breached the trust of the people of Illinois and his party far too often, doing great harm to our country," Marter warned while saying he supported Senate GOP efforts to block any Obama appointment.

Kirk has a big money advantage over all of his rivals in the race and also has the support of Republican Gov. Bruce Rauner. Several former Kirk staffers are top aides for the governor.

Illinois has witnessed one senator's political career derailed by a Supreme Court nomination. When the late Democratic Sen. Alan Dixon backed Republican President George H.W. Bush's successful nomination of conservative Clarence Thomas to the high court, then-Cook County Recorder of Deeds Carol Moseley Braun got into the 1992 primary and won a three-way contest before triumphing in the general election.

"Of course I was beat because I voted for Clarence Thomas," Dixon said in an interview connected with the 2013 release of his biography, "The Gentleman from Illinois."

The Senate seat held by Dixon, then Braun, eventually went to Obama and is now held by Kirk.

A version of this article appeared in print on February 16, 2016, in the News section of the Chicago Tribune with the headline "High court vacancy puts pressure on GOP's Kirk" —
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